1. Field of the Invention
The present invention relates generally to a guidance system, and in particular to a solid state guidance system configurable with a host projectile and operable within an extreme force launch shock environment.
2. Description of the Related Art
Currently available navigation, guidance, and control (NG&C) systems for projectiles, missiles, and space vehicles, that operate in benign flight environments, typically include GPS-based guidance systems combined with an inertial navigation system (INS). Typical INS systems include an inertial measurement unit (IMU) designed to measure motions of a host vehicle. In many systems, the IMU unit measures the swing of the proof masses of its accelerometers to infer translational accelerations of the host vehicle. Similarly, the IMU unit measures the movement of its spinning gyroscopes about their respective axes to calculate rotational rates.
The accuracy of IMU-derived data is therefore reliant upon the accuracy of its inertial sensors. However, in some applications such as non-thrusted projectiles, the accelerations are extremely high (approximately 15,000 Gs–20,000 Gs). Not surprisingly, the inertial sensors of the IMU system (swinging proof masses and spinning gyroscopes) are susceptible to failure. To improve the reliability of these systems, the design of IMU system components undergo a process known as G-hardening, which is an extremely expensive process. However, even after the IMU components have undergone a G-hardening process, these components are susceptible to failure when subjected to extreme G-forces. While there have been attempts to design durable and reliable guidance systems that may be configured with thrusted and non-thrusted flight vehicles, these attempts have not been entirely successful.